The acne gut: How to address the root cause of acne

When I was travelling in Australia, I left bright-eyed and bushy-tailed. At 21 years old, the world was my oyster. I had been saving up for the trip, and for the first time in my life, I had seen a nutritionist to help with my alopecia and psoriasis. Within three months of following the recommendations, I had already seen incredible results.

However, after several months of travelling, indulging in fast food, sugar, and sleeping in youth hostels, my skin started to break out. At first, it was just slight bumps on my forehead, but after a few weeks, my skin erupted in an angry rash. A visit to the doctor confirmed I had acne.

But, as always, there’s more to the story than meets the eye. Did I catch something from the countless hostel pillowcases I slept on? Was I allergic to the southern hemisphere sun? Or could it be my gut? What do you think?

Acne is often viewed as a surface issue caused by clogged pores, excess oil, or hormonal imbalances. However, research increasingly shows a strong connection between acne and the health of your gut.

The balance of bacteria in your gut - your gut microbiome - plays a critical role in managing inflammation, immunity, and even hormone regulation, all of which directly impact your skin.

Fast food, sugar and alcohol create the perfect storm for bacterial overgrowth, leaky gut syndrome, and inflammation. In this article, let’s explore how gut imbalances, particularly bacterial dysbiosis, contribute to acne and how the location of your acne may provide clues about underlying gut issues.

The gut-skin connection and the role of bacteria

The “gut-skin axis” is the two-way communication between your gut and skin. An imbalanced gut microbiome (a state called dysbiosis) can lead to inflammation that shows up on your skin in the form of acne. There are critical bacterial strains that, when out of balance, can worsen acne or trigger breakouts, and these are strains I often look out for when I am working with clients with acne. 

One of them is akkermansia muciniphila which is associated with gut barrier function and reducing inflammation. Low levels of akkermansia are linked to increased intestinal permeability (leaky gut), which can lead to systemic inflammation and skin flare-ups, including acne.

You also have some of the most researched gut bacteria, bifidobacterium and lactobacillus. These beneficial bacteria help maintain gut integrity and reduce inflammation. When these bacteria are low, harmful bacteria can flourish, leading to conditions like small intestinal bacterial overgrowth (SIBO), which has been linked to acne, especially those seen on the back or chest.

And it isn’t only to do the strains of bacteria, their balance is key as well. In particular the balance of firmicutes and bacteroidetes. An imbalance in the ratio of these two bacterial groups can drive inflammation and metabolic dysfunction, both of which are related to skin issues. A higher ratio of firmicutes to bacteroidetes has been associated with obesity and inflammatory conditions, including acne.

And lastly, propionibacterium acnes may also be a factor. While this bacterium is found on the skin, gut health can influence its overgrowth. When the gut is inflamed or imbalanced, it can exacerbate the skin’s production of oil (sebum), creating a breeding ground for P. acnes, the bacterium most commonly associated with acne breakouts.

Symptoms of gut imbalances 

What I hadn’t considered while travelling was that the digestive symptoms I was experiencing were directly linked to my skin. We had started our journey in Southeast Asia, where everyone caught some form of stomach bug along the way. Looking back, this may have been one of the triggers for my breakouts, with the poor diet I was eating only exacerbating its impact on my body.

As a 21-year-old, I wasn’t on the lookout for digestive symptoms, but there are often some obvious signs that your gut is out of balance. For example, if you have leaky gut syndrome, you often experience symptoms such as bloating, food sensitivities, brain fog, fatigue, and joint pain. And as for your skin, acne around the mouth, chin, and jawline is often linked to leaky gut and hormonal imbalances. A compromised gut barrier can lead to systemic inflammation, which may worsen cystic acne in these areas.

Then there is SIBO, with symptoms such as bloating, diarrhoea, or constipation, especially after meals. Skin manifestations of SIBO can cause acne, primarily on the forehead, cheeks, and upper back. Back acne is commonly associated with gut dysbiosis, particularly when there’s an overgrowth of bacteria in the small intestine that releases toxins into the bloodstream, leading to skin breakouts.

Gut dysbiosis is also typically a factor - symptoms such as irregular bowel movements, frequent bloating, sugar cravings, and difficulty concentrating may be a good indication that this is an issue for you and is often linked to acne on the cheeks and back. Cheek acne has been connected to poor digestion and bacterial imbalances, while back acne suggests a more systemic gut issue that may involve SIBO or candida overgrowth.

Lastly, candida overgrowth can present as fatigue, brain fog, sugar cravings, white coating on the tongue, and recurring yeast infections. Fungal acne can appear as small, itchy bumps that are often mistaken for regular acne. It can affect the chest, back, and even the arms.

Knowing the cause of your acne is vital so you can address this head-on and prevent further acne breakouts. 

What does back acne indicate?

One symptom I see a lot in my clients is back acne. My clients may come to me for their autoimmune conditions, and if it is paired with back acne, it gives me an excellent idea of what might be driving both their acne and autoimmune symptoms. 

Back acne is a strong indicator of systemic inflammation, often rooted in gut dysbiosis or SIBO. Unlike facial acne, which may be driven by localised hormonal factors or surface bacteria, back acne suggests that there is something deeper going on in the gut. When harmful bacteria or yeast overgrow in the intestines, they release toxins that can enter the bloodstream and show up as inflammation on the skin, particularly on the upper back.

Back acne can also be exacerbated by poor detoxification, where the liver and gut aren’t efficiently processing and eliminating toxins. This pushes the skin to take on the role of detoxification, leading to inflammation and acne. And that is why people with back acne might benefit from gut-healing protocols and liver support, similar to autoimmune conditions.

How to heal your gut for healthier skin

If you’re experiencing gut-related acne, healing your gut can significantly improve your skin. 

When I was in Australia, I was given antibiotics, which I unfortunately took for years after this, which probably impacted other areas of my health. However, after I restored my gut function, I have not experienced any acne since, after ten years of struggling with flare-ups. 

As with most conditions, knowing what is driving your symptoms is key to resolving them. Still, by focusing on anti-inflammatory, gut-healing foods like bone broth, leafy greens, fermented foods (like kimchi and sauerkraut), and high-fibre vegetables, you can start taking steps to improve your gut and skin health. These foods help repair the gut lining and support a healthy microbiome.

If your gut is ready for them, introducing beneficial bacteria through probiotic-rich foods like yoghurt, kefir, and supplements can restore balance in your gut. Strains like lactobacillus acidophilus and bifidobacterium bifidum have been shown to improve skin health and reduce acne breakouts, but go gently. If you notice that these foods are making your symptoms worse, then you may need to dig deeper to address the root cause. 

When I was travelling, my daily habit of eating a large bag of jelly sweets certainly didn’t help resolve my acne symptoms. Sugar, refined carbohydrates, and processed foods feed harmful bacteria and yeast like candida. Reducing sugar can starve these pathogens and help restore balance to your gut microbiome.

Remember your liver health. I see this as an underlying factor for many of my clients with skin issues. Improving liver function with supplements like dandelion tinctures and eating cruciferous vegetables (broccoli, cauliflower, kale) can help your body eliminate toxins more effectively. Better detoxification means fewer toxins circulating in your system, reducing the risk of acne.

Lastly, managing your stress levels and living in a calmer state may help, too. Chronic stress disrupts gut function by increasing gut permeability (leaky gut) and triggering inflammatory responses. Practicing stress-reduction techniques like yoga, meditation, or deep breathing exercises can calm both your gut and your skin.

Acne is more than just a skin issue; it’s often a reflection of what’s happening inside your body, particularly in your gut. Imbalances in your gut microbiome can lead to systemic inflammation, hormonal imbalances, and poor detoxification, all of which contribute to acne. By focusing on gut healing - through diet, probiotics, and stress management - you can address the root cause of your skin issues and clear up acne naturally from the inside out.